Pc power supply dna1002 ic

[dr pepper]

I want to convert an atx power supply so that it has a single output, about 6v to 18v and be controlled from a dc voltage (power aupply for a ventilation fan).
I was expecting a standard ic in the supply but its a dna1002 and I'm having trouble finding a datasheet for it, has anyone had experience of one of these ic's?
I'm thinking that theres a feedback resistor divider and a reference voltage that I can tap into to adjust the output.
Not sure whether the regulation is on the 5v line or the 12v line, I dont think they are seperate on this unit, maybe the 5v rail has a switching reg from the 12v rail.

 

[alec_t]

If the '1002' part is generic then ONSemi do a NCP1002 switching regulator chip which might be similar.
https://www.google.co.uk/url?sa=t&r...oYGYBg&usg=AFQjCNH76qYIGk6P6IJs78YGGmCe-KOxfg

 

[dr pepper]

Thanks Al.
My device is a smd and its 16pin, however I think its just a diffo package of the same chip.
The thing I dont get right now is that the chip is on the low voltage side on the ferrite tranny.
I'm thinking maybe this chip is the part of the circuit that converts 12v from the main output down to 5v.
Theres another device in there on the high voltage side I'll look into what that chip is next.

Edit: the primary side controller is a 1001dl, and apparently this is a custom chip made for microsoft (even though the psu is a dell?) and info is impossible to get, its a pwm controller thats all I found.
I think I'll pull another psu out of my stack of scrap bits and look at that one.